Reese Witherspoon is apparently determined to get back into her pre-pregnancy clothes.

The 36-year-old actress gave birth to her first child with husband Jim Toth, a son called Tennessee, four months ago. Reese has already been spotted in public looking trim, and the health conscious star is eager to snap back into shape.

“Reese doesn’t give herself enough credit for shaping up,” a source told British magazine Closer. She knows she looks great, but wants to get down to her pre-pregnancy [UK] size 8 eventually.”

Reese was recently seen on a beach in Hawaii, wearing a ruffled navy swimsuit. The actress’ figure is impressively toned, which is down to her healthy attitude to food and exercise.

Reese remained active and ate sensibly throughout her pregnancy and the hard work is paying off for the mom-of-three.

“Reese loves to jog and she is yoga addict,” the source added. “So while she was pregnant, she took a 90-minute yoga class up to three times a week at her home, and ran three or four times a week. She also ate lots of fruit, fresh vegetables, fish and wholegrain foods. Reese doesn’t need to crash diet or do anything crazy at the gym – she didn’t gain much to begin with.”

In December, Reese joked that she was “slowly crawling back” to regaining her pre-pregnancy body.